What is the Difference Between Isostructural and Isomorphous?

The terms isostructural and isomorphous are used to describe different structures in chemistry, and while they may sound similar, they have distinct meanings:

• Isostructural: Two crystals are said to be isostructural if they have the same structure, but not necessarily the same cell dimensions nor the same chemical composition. In other words, isostructural compounds have similar chemical structures, but their physical dimensions and compositions may differ.
• Isomorphous: Two crystalline solids are considered isomorphous if they have the same unit-cell dimensions and space group. In addition to the same atomic connectivity that characterizes isostructural compounds, isomorphous substances also crystallize in the same space group and have the same unit cell dimensions.

In summary, the key difference between isostructural and isomorphous is that isostructural refers to having a similar structure, while isomorphous refers to being able to crystallize in a form similar to that of another substance, with the same unit-cell dimensions and space group.

Comparative Table: Isostructural vs Isomorphous

Isostructural and isomorphous are two different terms used in chemistry to describe the structures of crystals. Here is a table summarizing the differences between isostructural and isomorphous:

In summary, isostructural crystals have the same structure but may have different cell dimensions and chemical compositions, while isomorphous crystals have the same unit-cell dimensions and space but may have different structural arrangements of molecules.